1. Field of the Invention
This invention relates to a multi-layered blister package having a cavity with a depth that makes removal of articles contained within the package difficult for children.
2. Discussion of Related Art
It is common practice to use blister packages to package small solid articles or products which may be dispensed from the package by applying pressure to the blister to force the article or product from an individual blister or capsule through a rupturable membrane. Since this type of packaging is typically used for marketing medicines, the invention will be referred to herein with respect to a package particularly suitable for such use, but it should be understood that the package may be used for other products as well. Recently, a substantial effort has been directed toward providing packaging that contains sufficient impediments to prevent children from easily opening the package and gaining access to the package articles or products while still providing adults with easy access to the articles or products contained therein.
For example, U.S. Pat. No. 6,161,699 to Gartland discloses a conventional child-resistant package 10 having a blister containing laminate 12 with a plurality of cavity forming blisters 14 provided therein and projecting from a top of the laminate 12. As illustrated in FIGS. 1-4 of Gartland, each blister 14 includes a tablet or pill 16. A foil sheet 18 seals the blister 14 with the pill 16 therein. A card backing 20 is then laminated onto the other surface of the foil 18 and is formed with a series of punch-out sections 22 that are aligned with the blisters 14. Each punch out section 22 has perforations 24. A high strength adhesive film 26 is laminated onto the back of the card 20. The adhesive film 26 is then removed to expose the punch-outs 22 formed by the perforations 24 in the card backing 20. Then, in order to remove the pill 16 from the blister 14, pressure is applied to the blister 14 so the pill punctures the foil 18.
Gartland's package requires a rather undesirable level of dexterity on the part of a user attempting to gain access to the pill 16 in that the user must somehow peel the adhesive film 26 off the back of the card 20 before applying pressure to the blister 14. Presumably, the user will have to slide a fingernail or other thin device, such as a knife, between the film 26 and card 20 so as to peel the film 26 off the card 20. Adults, particularly the elderly, may not have the dexterity, hand eye coordination, or patience necessary to peel the film 26 off the back of the card 20, especially those that suffer from arthritis, poor vision, and other such ailments.
U.S. Pat. No. 5,758,774 to LeBlong discloses another example of a conventional child resistant blister package. In particular, LeBlong discloses a convertible child-resistant blister package 10 that includes a first thermo-formable layer 11 bonded onto a second layer 12 formed from a rupturable material, such as, for example, foil. A blister 15 containing a tablet or pill 16 is provided in the first layer 11. A third layer 17 is adhered to a bottom of the second layer 12 with a fourth layer 20 adhered to the back of the third layer 17. A release peel coating is provided between the third layer 17 and the second layer 12 so that the third layer 17 can be peeled off the second layer 12.
Furthermore, the third and fourth layers 17 and 20 are integral so that when the third layer 17 is peeled off the second layer 12, both the third and fourth layers 17 and 20 are removed together. Tear slits 21 extend through all four layers to provide access to the individual blisters 15. Therefore, in order to gain access to the tablet or pill 16, a detachable section 22 provided at the end of the package 10 is removed exposing the end 26 of a perforated strip 27 provided in the third and fourth layers 17 and 20. See FIG. 2 of LeBlong. Then, the longitudinally extending perforated strip 27 is removed exposing the rupturable second layer 12 through which the row of tablets 16 can be pushed. See FIG. 4 of LeBlong.
It is well known in the industry that child resistant features in such packaging is most effective when provided toward a center of the package away from the edge of the package as such placement restricts children from biting through the edge of the package to gain access to the article or product provided therein. In other words, when removable portions of the child resistant feature are provided along the outer edge of the package, it has been found that children are able to access the articles or products simply by biting through the outer edge of the package. Leblong's package enables children to access any unused pills 16 provided beneath the perforated strip 27 as the end 26 of the strip becomes the edge of the package 10 after the detachable portion 22 is removed.
U.S. Pat. No. 5,339,960 to Price discloses yet another example of a conventional child resistant blister package. It should be noted that the Price package positions the child resistant feature at the outer edge of the package. Specifically, Price discloses a child resistant package 10 having a body 11 that contains a plurality of blister chambers 12 with a pill 13 provided therein. The package 10 includes panels A, B, and C. Panel C is folded over panel B and then panel A is folded over panel C. See FIG. 3 of Price. Panel B includes oval cutouts 36 through which the blister 12 extends. Panel C includes score lines 48 and 50 that align with the oval cutouts 36 in panel B. Likewise, panel A includes score lines 18 that align with the score lines 48 of panel C and oval cutouts 36 of panel B. Panel A also includes a tab 15 with a peel away access panel 17 formed by the score lines 18 and 45.
To gain access to the pill 13, the tab 15 and peel away access panel 17 on the outer edge of the package are removed to expose a bendable breakaway panel 21. The bendable breakaway panel 21 is then removed exposing a rupturable foil barrier 19. Then, pressure is applied to the blister chamber 12 such that the pill 13 can penetrate through the foil barrier 19. See FIG. 2 of Price.